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New Grow Hack Increases THC Levels By 28%

Designed Specifically For
Horticulture Applications

Cannabis Researchers in Maryland exposed Cannabis Sativa plants to Ultraviolet radiation to see what would happen. They found that increasing doses of Ultraviolet Light, specifically UV-B spectrum light, a natural part of sunlight, caused the plants to produce almost 28% more THC.

The Ultraviolet (UV) light spectrum ranges from about 100 nanometers (nm) to 400 nm. UVA, ranges from about 315 nm to 400 nm. UVB ranges from about 280 nm to 315 nm, is somewhat damaging to plants in high levels and causes sunburns on humans.

UVB causes damage in plants in much the same way as it damages human skin. Plants created defenses against UVB in the form of a protein called UVR8. UVR8 is a protein molecule which senses UV, and then “tells” plant cells to change their behavior. One of these changes caused by this reaction is very important in a Cannabis garden. UV stress stimulates cannabis’ production of chemicals via the phenylpropanoid pathway, specifically malonyl-CoA and phenylalanine. Why is this important? Because cannabis uses malonyl-CoA to make Olivtol, which it in turn uses to make THC. So finally the specific pathway which increases Cannabis potency when exposed to UV light is understood, and smart growers can use this information to their advantage.

UVB light is completely absent in all traditional Grow Light sources, including High Pressure Sodium, Metal Halide and even the latest Ceramic Metal Halide and L.E.D. lamps. When lamp companies claim “UV” output, they are almost always discussing UV-A light spectrums. Testing has shown the UV-B output of any of these lighting sources to be near zero. The AgroMax PureUV lamps however are specifically designed for production of UV-B lighting spectrums which are the spectrums which are required to create the UVR8 reactions. The AgroMax PureUV lamps produce about 75% of their output in the UV-B range and 25% in the UV-A range. The AgroMax PureUV lamps are constructed of special glass that allows the transmission of the UV light.

It has been reported by users of the AgroMax PureUV lamps that correct usage of the lamp will not only dramatically increase THC levels but also improve resin production and flavors. Advanced growers are aware of the benefits of UVB and use the AgroMax Pure UV lamps to boost potency. However, be aware, there is a threshold where the damage to yield caused by high levels of UVB will exceed any benefits in potency, so caution and careful design protocols MUST be used when attempting to supplement UVB.


AgroMax PureUV grow lamps have been used in commercial and home gardens with fantastic results for the past 2 years. The following are some “recipes” shared with us:


For Increasing THC Levels

I use the AgroMax PureUV lamps in the later stage of flowering, for about 15 minutes 3-4 times in the 12 hour cycle. They work very well and I am blown away by the results. I use 2 lamp fixtures mounted about 4 feet above my plant canopy.

I hang my 1 lamp T5 lamps equipped with AgroMax PureUV lamps about 3’-4’ above the canopy and run them for about 15 minutes per hour during flowering. I used to use the Reptile T5 lamps, but I know the PureUV’s are about 4 times more powerful, so now I need less lamps and less on-time which is good for when I need to work in the garden. I just use 1 fixture for about a 6×6 area. These lamps really jack up my THC levels. My buddy has a similar setup but uses his old light mover to move the fixture around and can have the light on for about 30 minutes of every hour.

I use the PureUV lamp for the last 10-14 days of the flower cycle, running them on 15 minutes on/30 minutes off cycles for 3 hours per day. I have them on during the middle of the light cycle to simulate peak sunlight. I experience extreme increases to flavors, oils and resin production. The PureUV lamp is the least costly and single best improvement I have ever made to my garden, including upgrading nutrients, innoculants, LED’s, CMH, etc.

I see great results when I use the AgroMax PureUV lamps. I have several single lamp 4’ Pure UV scattered about 3 feet above the canopy and cycling on for 10min each hour. I saw a noticeable difference in the oil production of the flowers that were closer to the lamps. I will say that a hardening off period is necessary with these lamps and plants can take longer exposure as they become adjusted to the UV-B.

For Indoor Plants About to be Moved Outdoors


I start my gardens indoors using mostly fluorescent lighting. I have found that supplementing my lights with the AgroMax PureUV lamp helps to harden off my plants before placing them outside. I use a timer and have the UV light on for only 5 minutes twice a day, during the middle of the day. The 1 lamp T-5 fixture is about 3’ away from the plants.

For Fungal Problems, Powdery Mildew and Botrytis


After reading the Cornell study, I wanted to try more natural ways to treat and prevent Powdery Mildew. Research shows that the PM fungus is especially vulnerable to UV-B light. The AgroMax PureUV lamp helps me control and destroy powdery mildew. I use the lights during the flower stage at 5 minutes per hour. Used correctly it will completely prevent PM, and used after an infection, it quickly reduces PM and eventually destroys it.